1. Field of the Invention
The present invention relates to rotary pulsing valves for whirlpool spas.
2. Background of the Invention
Whirlpool spas or jacuzzis typically contain one or more wall-mounted water jets for massaging an occupant of the spa. A more effective massage may be provided if several jets are located near each other in a cluster and the water flow is sequentially switched between individual jets in the cluster. This switching may be accomplished by a multiplexing or pulsing valve.
One such valve has been sold under the name CYCLE-JET. The CYCLE-JET valve includes a turbine wheel driven by water flow from the valve inlet. The turbine wheel contains a number of openings which shunt water to output openings of the valve connected to the individual water jets. As the turbine wheel rotates, the openings in the turbine wheel align themselves with individual openings in the valve which are connected to the output openings, thereby allowing water to flow from the valve inlet into one of the outlet openings at a time. Rotation of the turbine results in the selection of different output openings, and therefore different water jets. The valve therefore allows the location of water flow to move about within the cluster of water jets rather than being fixed at a single location. This feature allows the water jets to massage a larger area of the spa occupant's body.
Although it allows movement of the massaging water jet, the CYCLE-JET valve suffers from operational difficulties. Rotation of the CYCLE-JET's turbine wheel is easily impeded by the accumulation of small grains of sand or grit between the turbine wheel and the valve housing. Such accumulations of small amounts of contaminants cause the turbine wheel to seize, thereby halting the valve's switching operation. Because the CYCLE-JET is typically mounted in the ground near the whirlpool, removing sand accumulations from a seized valve is often a difficult task.
Additionally, the CYCLE-JET does not allow its user to independently vary the speed of switching and force of water emitted from the jets because water flow from the valve inlet also drives the switching mechanism. Output water pressure and switching speed are therefore inextricably related to each other and may not be varied independently.
Consequently, a reliable pulsing valve which sequentially switches an inlet water stream among individual jets for massaging the occupant of a whirlpool is desirable.